The ACU-FLAP Check Element is an elastomeric flap mounted over a rectangular concrete opening. In the rest position the elastomeric flap is bolted along the top edge of its stainless steel mounting frame, thereby closing and sealing the opening. If the water level in the sewer or tank overflow rises, the hydrostatic pressure against the ACU-FLAP Check Element causes it to open thereby allowing the water to flow over the sill. If the downstream water level rises, the ACU-FLAP is pressed against its stainless steel mounting frame so that no water can flow back into the sewer system, tank or basin. The ACU-FLAP’s lightweight design makes it highly responsive to minimal water level changes while ensuring structural stability under medium downstream water level conditions.
The ACU-FLAP Check Element is equipped with an integral stainless steel frame for anchoring to the concrete structure. This flat and smooth sealing-surface increases the tightness of the flap and avoids the potential problems caused by irregular concrete openings and surfaces.
The ACU-FLAP Check Element can be fitted with a stainless steel plate for extra rigidity and weight to improve odor control and accommodate higher back water conditions.